Wireless terminal devices having wireless functions, such as mobile phones, have technologies with which, by regarding circuit boards inside housings as conductors and by integrating these into some sections of dipole antennas, radiation characteristics of the antennas are improved. For example, in the patent document 1, wireless terminal devices in which, by establishing conductivity with the ground of the respective circuit boards using a connecting section of an upper housing and a lower housing, the full length of the dipole antenna is deployed, and in which the radiation characteristics are improved even in the state in which the housings are open, are disclosed. Moreover, in the patent document 2, it has been disclosed that by electrically connecting the circuit component that is mounted on the lower circuit boards of the lower housing to the circuit component that is mounted on the upper circuit board of the upper housing with flexible cables, the full length of the dipole antenna is deployed.